Flat panel displays are currently the most popular display. Among the flat panel displays, active matrix organic light emitting diode (AMOLED) display apparatus has been widely used in electronic products such as computer screen, mobile phone and so on, due to its characteristics such as light and thin outline, saving electricity, no irradiation and so on.
AMOLED display panel mainly comprises an array substrate, a chip on film (COF), and a printed circuit board (PCB). The array substrate comprises a display region used to perform displaying and a connection region (that is, Fan Out) located at the periphery of the display region. End heads of leads in the display region are located in the connection region. Leads and a chip are disposed on one side of the COF, and the leads of the connection region of the array substrate are connected to the PCB by these leads and chip.
As illustrated in FIG. 1, preparing a conventional AMOLED display panel comprises: firstly attaching a surface of the COF 200 disposed with a chip 201 on the connection region 400 of the array substrate 100, wherein the connection region 400 is formed at the segment difference between the array substrate 100 and an package layer 101; then attaching the other end of the surface of the COF 200 on the PCB 300; subsequently folding the COF 200 by 180°, so that the PCB 300 is disposed on the back side of the array substrate 100 (i.e. the side which does not emit light), at this time, the chip 201 on the COF 200 is disposed towards a side away from the array substrate 100. When assembling the display panel, it is required to not only guarantee the occupation space of the COF 200, but also guarantee the safety of the chip 201 on the COF 200, since the chip 201 should not be pressured and should not contact metal. Since the existence of the folding region of the COF 200, the frame of the display apparatus has to leave enough space, to place not only the COF 200 but also a glue frame and an iron frame, so that it causes the frame of the display apparatus to be too wide; meanwhile, a distance between the PCB 300 and the array substrate 100 should be at least equal to the diameter of the folding region of the COF 200, so the PCB 300 may not be disposed close to the array substrate 100, so that it causes a problem that the thickness of the display apparatus is too large.
In addition, since the COF 200 is attached on the surface of the PCB 300 facing the array substrate 100, wires of the surface are transverse wires, and wires of the surface of the PCB 300 away from the array substrate 100 are vertical wires (here, the wires perpendicular to the paper plane is called as vertical wire, and the wires perpendicular to the vertical wire and parallel to the circuit board is called as transverse wire). The vertical wires are mainly used to transfer signals between respective electronic components 301 of the PCB 300, and the transverse wires are mainly used to connect the electronic components 301 to the bonding pins. In order to avoid the electronic components 301 on the PCB from being damaged, the electronic components 301 are generally disposed on a surface away from the array substrate 100; however, in this way, it would compete in space with the vertical wires, causing difficulty in wiring.